Sound modulator for phonographs



N. SEAHOLM.

SOUND MODULATION FOR PHONOGRAPHS.- APPLICATION msu Dc.24, 1920.

1 ,414,673.' Patented May 2, 1922.

IIIIIIIIIIIIIIIIIHHHI TMS urns snan'oinu, Aor' Monivrvnniioiv, NEW YORK.

souivn monomarca non' Pieio'noenarns.

targeta;

vSpecncationof Letters latent.

Patented tray a', ieee.

Application inea December 24; 1920; serial N; eeajeai.

To-LZZ whom t may concern.' f 1 Be it4 known that N'iLs `SEAHOLM,y 'acitizen of the United States, and a resident of the vcity ofMountVernon, in the Vcounty of'l/Ve'stchester and State of' New York,have invented certain-new and'useful lmprovements in" Sound Modulators'for Phon'ographs, of which the following vis a sp'eciii'- cation." d YThisinvention` relatesA to a modulator or sound 'modiiier 'forgraph'ophones or"` phonograph's andthe like. It morepartifcularlyappertains tol adevice interposed between the stylus of ay soundreproducing machine' and the sound box thereof by means of which theaudibility of the acoustic waves may be regulated.y p

@ne of the objects of the invention'is to provide a device ot thecharacter describes Which is applicable to' different makes' otphonographs now` in use and capable 0faccommodating various types otneedles for the same.l

Another object is Vto produce a device of the nature set forth wherebythe reproduction of sound from' a record can 'bev rendered in anydesired degree ofi softness andwithout muiliing it, at such times when`it is vdesirable to keep the sound from'. reaching adj oin'ing' rooms.

A further object is the production of va device' of the type speciiiedwherein the weight ot the sound box is resiliently carried andirregularities occurring in the various'movements,between the stylus andthe record vare compensated in order to obviate excessivewearupon thelatter. A

Still :mother objectv is the provision of a device oit the' classmentioned enabling the intensity of the sound to be regulated inproportion to an interposed resistance', while the recordvis beingplayed.

A-still further ob"ect Ain producing 'a devicel ofthespecies're'fei'fr'ec'lto, is the embodiment of means'tforjadjusting the angularinclination of the stylus" relatively to the s'ond grooves inraccordance 'with' the audibility desired but without alteringtheleverage of the stylusor' changing'fthe position. thereof within itsholding socket.-

An additional object iste sup/plyl a de-v vice of the genus alludedltoconiposed of few, simple and durablefpjarts," quickly'and easilyassembled and 'of low manufacturing cost,:not` liable to getH out oforder,- and which lmay be readily installedl as well as operated by'-the average person.

Other objects and yadvantages of the inventionwill become apparent asthe specifi` cation proceeds. lVith` theM aforesaid objects in view,.theinvention Vconsistsv of the novel combinations and arrangements of partshereinafter described in' their preferredl embo-diments, pointed out' inthe subjoined claims, and illustrated on'- thev annexed drawing, whereinlike parts are designated by the same reierencechara'cters throughoutthe several views: f

In the said drawings f Figureis a side elevation showing this improvedfdevice in operative 'position with respect to a sound box andy ai'recordo't a phonograph of well knownftype;

. Figure Il isl an enlargedsectional elevation of the device alone, in aposition-conducive to the maximum softening' of the sound.

Figure HIis'a top plan view ofthe device shown in ythe' precedingfigure; v

Figure IV is va view similar to Il,

showing the device in' a position vcorresponding toa minimum ottonesuppression; and Figure V is a rearl elevation ofthe device intheposition vseen in-tli'e`last named view.

`Generally' described, the invention includes in its organization 'apair of spaced, Iii'ngedly connected'members. From' one of the latterextends a Yshank adapted or'insertion into Athe needlefsoclretiotaphonograph, while the other one of its `members affords Va socketcap'ableoif receiving an `ordinary stylus. Diiferentially actingresilient elements interposed between these members tend 'to maintain-them f inZ f normal position.' means isprovided for' varying vtheinterrelative' rigidity of the 'elements andfthereby change theamplitude of the sound transmittedy from the stylus to the soundboar".throughl the' members, adjustment' of'the same being limited'bystops formingwith the Ymeans above mentioned a continuous' pathI Jforthe sound waves.

"The advantages "of the invention as here outline-d are bestv realizedwhen all of its features and instrumentalities are combined inthe oneand samev structure, b ut useful devices may be produced embodying-dessthan the' lwholeL'V re.Wiiibefobviouefa moge-.Sealed iai-ae art tovwhichthe'invention appertains, upon rbecoming conversant with the detailsthereof, that the same may be incorporated in several differentconstructions; n panying drawing, therefore, is vsubmitted merely 'asshowing the preferred exemplification of the invention.

Referring now to the several views of the drawing for a detaileddescription of the invention and in which the known elements Y of asound reproducingmachine have been indicated in ldot-and-dash lines, thereference letter A- denotes. a sound `box carried from a sound arm B andhaving a vibra-tory diaphragm C. D designates a vibrating .leverfastened at one end to the diaphragm @fand ,having at its oppositeextremity a socket E ordinarily` adapted to y'receive a stylus. Thislever is fulcrumed intermediately of its ends to the sound box A. as atF. G is a thumb-screw for holding the shank of the stylus in the socketE. A record Hv of the fiat disc variety'isrshown'-supported by a turntable J which is rotatable overa cabinet K. iv

11 designates a relatively fixed'member to which a companion member 12`'is movably connected, as for eXample,;by-a hinge pin 14 pivotallycoupling opposed inwardly facing ears 15 and lwherewith the members 11and 12 are provided. o Near or at the corresponding ends of themembers11 and 12 are outwardly projecting portions or lugs 19, 20. y From kthefirst named lug 19 extends a shank 21 in substantial pa-rallelismwiththe member 11 and adapted forv insertion intro the socket E of the leverD. Y 'f vl'n the lug 2O is a socket 22 substantially parallel with themember 12 adapted for the reception* of alstylus or needle L which isheldin place therein by ay thiunb-screw'23 operableby means of a knurledhead 24 or otherwise as may be desired. l The socket 22 thereforejservesthe purpose for which the socket E was designed. y 'j -Y f As indicatedin FigspI and II, 'the members 11 and 12 are maintained in .normalposition by one or more" resilient element-s 26. and 27 which, as shown,may be helical compression springs loca-tedrat different distances fromthe pivotVo-rt fulcrum po-int' 14.

Thespring-26, which is at agreaterdistance from-this fulcrum andtherefore acts'with a longer leverage may preferablyhavercoils ofsmallerrsize and of lighter wire thanv the spring 27, the latter beingof heavier wire wound 'v into coils of a slightly larger diam"- l eterandfis for that reason the stronger.

But', as the same is placed nearer the pivotal point 14 it exerts aresistance equal to-26 thus, serving to balance the latter; and tomaintain the members 11 and 12 normally` Vin equipoise.

ljhis arrangement of diferentiallyacting .Seuils elements has beentcindiiiiiiiactice The accom# to give the best results inV transmissionofV sound in a device of this character.

As will be apparent from Figs. H and IV, the elements l26, 27 have theiropposite terminals received within recesses or cavities formediin ,theklug 19 of the member 11.

Toy differentiate the action of the springs 28, 29YY and 30, 81 in themembers 11, 12. VThe first/.named recess 28 which is the deepjest forthev reception. of tine spring 26 is 26, 27, a thumb-screwBS havingvan'easily manipulated head 34 is provided.l This screw is threadedintol theilug 19 and located so as to exei'tan endwise thrust upon; thevcorresponding terminal ofthe spring V26 when driven into the recess,28.Thefurther the screw 33 is forced against the spring yeley men't26, thegreaterrwill be the pressure applied on the element 27 as well, and'theabove the stylus L, any backlash 4.occurring between the parts is takencare of, this vbeing conducive to a constantvr transmission of thesound.V f f Moreover, owing to the rearwardly offset disposition of-thisattachment, the overhang thereof is reduced to aminimuin while theposition of the stylus L and its inclination is kept Aas nearly aspossibleV the .saniewith respect to aline passing'vertically through the`centenofthe sound box A as when the E of the sound lever D". fr Y f fBln order to limit the convergency between the members 11 Vand 12suitablev stops are provided. The-same Ycomprise preferably,

stylus'L is inserted directly into thesocket i headed pins 3,5, `36,"having their shank' por-l tions passing through-the springsV 26, .'27respeetively,

springs-onone end. As shown in FigyIl-the point of the screw 33T-abritedirectly againstthefhead ofV while theirheads overlie the pin 35, andin. the-innermost position of the said screw,'the' headless end ofthe-.pin 35 is pressedgto tlierbottom'of the recess 29. At the same timeas this occurs both ends of izo the pin 36 are forced against thebottom'of their respective recesses, being squeezed be-y tween theshorterilever arms of the members 1 1, 12 which are thereby lprecludedfrom further movement.

.In ythis lastfposition the members *11,712V Y areobviously relativelyimmovable,v being held fromfpartakingf of independent `oscillaf rigidlyLconnect; these. members consist of the; screw 36 pressing' thereontogether withy thepins 35,' 36.f

Auxiliary means fare provided for adding graduated increase ofresistance to that of the springs 26,27 against tilting 'of the membersv11 and..12. This latter meansi is' arrangedftoact shortlyiin advance ofthev mem! bers 11 and` 12 being; lockedtogether. To this'enda pair ofLfshaped springs have their toe portions 38, 39'inserted into anaperture yprovided therefor in the member 12 slightlybeyondthe pivot 14yon the shorterflegof thememberili. Legs 40, 41 of these supplementaryVspring elements are offset Withirespect toeach other, buttheendsLthereof are. brought up againstv a common stopl42yvhfich may-`consist ofafpindrivenl intoV theV member 11 in-.t proximity to the lug 19.r

The construction'isisuch that first oneY of the 'legs -41fis broughtintoContact with` the4 stop 42 at one side of .the memberllfand'if the'oscillatory movement of the member 12 is. continued, the otherleg4f) issubsequently forced'against the .pin 42 at .the opposite side ofthememberll. In thiscway the-gr C- uated resistance mentioned aboveisobtain'ed prior to'the`membersy11 and 12 reaching. theirdeadlockedposition. c

Preferably the ears 15, 16 are provided at the opposite faces With hubportions 43, 44 which are suitably grooved or channelled to receive thelegs 40, 41 of the said springs.

lVashers 45, 46 overlie the grooves that receive thefmiddle parts ofthelegs of the auxiliary springs and` serve to keep the latter in theirassigned positions. The extremities of the 'pin k14 vhi'ch pass throughthe said f Washers are headedor upset to retain them from displacement:

From the'foregoing it will be observed that the Working partsOfthedevice Vare disposed and operate in the' same plane as the originalstylus'socket'E which also coincides with the`A alteredor newl positionof the stylus D itself. rl`his arrangement'of parts insures fa balancedaction of the device.

'The'contactpoint of the stylus with the record H is. beyond the:pivotal yconnection 14' and all irregularities'or minute butmultitudinousimpacts produced by the record upon: the stylus arecompensated Aor absorbed bylthe springs 26, 2T, so that only a clearsound free from discordance is transmitted. fThereis nothing tofbe.tampered with or get out of order. The mere adjustment 'of asingl'escrew' Wi'llleither increase or decrease the inclination of thestyles to soften thereto adapted to receive a" stylus, and

means for varying the interrelative yrigidity between said members.

2. In a sound modulating device for phonographs andthe like, thecombination with the sound boX- and vibratory lever of the4 latter, of'ran attachment' comprisinga member having a part adapted to engage saidlever, another member flexibly Vconnected withv said first named memberand provided with a portion capable of receiving. a'sound reproducinoneedle, and means adjustable for varying degrees of: resiliency coactingwith said mem-bers.'`

3. ln a sound mod lator for-phonographs, thecombination with the'soundbox and vibrating lever of the latter, of a device comprising a pair offlexibly coacting pivoted members, one of said membersbeing adapted forvconnection with saidy lever, .vhile the other one thereoll is capable ofreceiving a sound*reproducing needle. and means for varyingtheflexibility ofaction4 between the said members.4

4.A In a sound modiilatoi'ffor phonographs and the like, the combinationwith the sound boX and'vibratory lever of the latter, of a devicecomprising a pair of flexibly coacting members, one of said membersbeing carried by said lever, ivhile the other one thereof is adapted toreceive a stylus, differentially acting means yconnected up with thesaid members, and other means for varyinglthe action of said first namedmeans.

` 5. ln a sound modulator for phonographs and the like. the combinationwith the sound bo\v and vibrator lever `of the latter, ofva deviceincluding flexibly joined membersioo and the like, the combination Withythe sound box and vibratory'lever ofthe latter, of a device including apair of flexibly coupled members supported from said -lever, oney ofsaid members being adapted to hold a styisoV CIK

lus, a resilient element connected up with the members, and means forvarying the resiliency of said element whereby the transmission of soundwaves between the-members maybe controlled.

7. In a sound modulator for phonographs and the like, the combinationwith the sound box and vibrating lever for the saine, of a Vdevicecomprising a pair of flexibly joined members supported from said lever,a stop on one of said members, one of said members Y being adapted tohold a stylus and carryingV =v which is adapted to hold a stylus, a stopon one of said members, a resilient element car- Y ried by the othermember capable otoffering resistance to the movement of the members byengaging said stop, a spring interposed between the said-members, andscrew means for diminishing the distance between the `members againstthe resistance of said spring and said resilient element. y i

, 9. In a sound modulator for phonographs, the combination with thesoundbox and its vibratory lever, of a devicecomprising a pair of.pivotally connected members supported from said lever, lone of saidmembers being adapted tofreceive av stylus, differentially actingresilient elements coupled up with the said members maintaining them innormalcy,'and adjustable means for varying' i the resiliency of saidelements to control the transmission of sound therethrough.

l0. In a sound. modulator for phonographs, the combination with thesound box and itsvibratory lever, of a device comprisying pivotallyconnected members supported from said lever, one of said members beingadapted to hold a stylus,-differentially acting resilient elementsintermediate of the said members maintaining them in normal position,stops coacting with the latter, and means for adjusting the resiliencyof said elements to vary the interrelativefflexibility between themembers, said means being capable also of forcing the latter into rigidcontact with said stops.'

11. A device of the character described comprising in combination, amember having a shank adaptedV to be'inserted into the stylus socket ofa phonograph, anothery member capable o f receiving a sound reproducingneedle pivotally'connected to said first named member', resilientelements in-` terposed between corresponding ends ofthe said members,the same being formed with;

recesses for thereception of said elements, stops intermediate otsaidends, and a screw entering one Vof said recesses arranged primarilyto vary the compression .upon said elements thereby controlling thevmembers" interrelative flexibility, and subsequently'V forcing thelatter into locking position with j said stops. i,

l2. A device of the characte'rr'described lcomprising in combination, amember hav! ing a shank designed for insertion into theA stylus socketof a phonograph,` another member capable of receiving asoundreproducingneedle pivotally connected to said first named member, theVcorresponding ends of said membershaving recesses therein, resilientelements interposedV between said ends and restingin said recesses, ascrew entering' one of the latter adapted tor vary the resistance of theVresilient .element therein and tok lock ythe said members together,stops on one of the members, and auxiliary means on the other membercooperating with said stops to increase the 'resistance between themembersy just prior to their becoming locked.

13. A device of the character described-V comprising in combination, apair ofvpivotally connected members, one of them having a shank arrangedfor insertion intok theineedle socket of' a phonograph, while the othervi oneis adapted to receive a stylus, springs of varied strengthinterposed between said:

members at different distances Y,from ntheir pivotal connection,stops'mounted infsaid springs intermediately of theV said members, and ascrew carried by one of the latter capable of regulating the action vofthe springs to control' the members interrelative flexibility,'and tovlforce the-same in rigid engagement with said stops.

la-L device of the character de scribed comprising in combination, a.pair of pivingV a shank arranged'for' insertion intoithe needle socket.of a phonograph, while the other vone is adapted to receive astylus,springs of varied strength-interposedibetween said members at different"distances from their pivotal connection, stops mounted i107A otallyconnected members,-one ofrthem hav-7- in said springs in termediatelyofthe said i members, a screw carried by one ofthe lat-1 ter capable lofregulatingvthe'interrelative action of the springs and the members andto bring the same into'locking engagement with said stops, and yanauxiliary spring' supported by one member in abutting'srelation to theother affording a graduallygincreasing resistance lprior to the membersbecoming locked.l

NiLs r'sisiuaeuiiifi,l

